Compact 3D vertical sidewalls (no tapering) for optimal sleeping surface area R-Value: 5.2 MegaMat Ultra combines the cradling comfort and 3D construction of MegaMat with the smaller pack size and light weight of a classic air mattress. It is a great option for campers who want to elevate their current sleep system while retaining portability and compactness. Synthetic insulation welded to the inside of the mat keeps you comfortable in all seasons, while the stretch tricot polyester surface material provides next-to-skin softness. Convenience features such as a welded grab handle and separate one-way inflate and deflate valves round out the mat.